Apple has bought the firm widely believed to be responsible for the design of the engine behind the A4 CPU that powers the iPad.

Apple has bought the firm widely believed to be responsible for the design of the engine behind the A4 CPU that powers the iPad. Intrinsity does not directly make microprocessosrs; instead, it specialises in designing and licensing high-performance chips for mobile applications.

In fact, its primary product is a set of design tools, called Fast14, which implement a number of sophisticated algorithms and techniques to improve the efficiency of CPUs based on a number of different architectures, including the ARM family that at the core of many of Apple's mobile devices.

In characteristic Apple fashion, the company has only now confirmed the purchase, although many of Intrinsity's employees had changed their online profiles on the business-oriented social network LinkedIn to reflect their new positions with the Cupertino giant earlier this month.

Apple hasn't detailed what it paid for Intrinsity or how it plans to use the chip designer's technologies. Company spokesman Steve Dowling told the New York Times that "Apple buys smaller technology companies from time to time, and we do not comment on our purpose or plans." The newspaper, however, cites an industry expert claiming that the acquisition set Apple back $121 million, chump change, really, for a company that ended its fiscal second quarter with $41.7 billion in cash and investments on hand.

This isn't the first time Apple has snapped up a chip specialist. In 2008, the company bought chip designer PA Semi for a reported $278 million.